Pipeline strainers are used for protecting pumps, compressors, turbines, meters, automatic valves, sprinkler heads, nozzles, steam traps, heat exchangers, meters, and other pipeline equipment.
Two common designs for pipeline strainers are the Y-shaped pipeline strainers (see, e.g., FIG. 3 of U.S. Pat. No. 5,718,822) and the basket pipeline strainer (see, e.g., FIG. 4 of U.S. Pat. No. 5,718,822). Most basket pipeline strainers are intended for horizontal or slightly inclined piping. On the other hand, the Y-shaped pipeline strainers, as well as some T-shaped basket strainers, can be used in horizontal, as well as vertical (downward), piping. In the Y-shaped pipeline strainers, a debris collection chamber, which houses a straining element, is disposed obliquely to the flow path of the fluid thorough the pipeline strainer.
In both types of designs for pipeline strainers, the pipeline strainers remove solids from a flowing fluid with a perforated, mesh, or wedge wire straining element. The solids are retained in the straining element, allowing the fluids to flow therethrough and to the downstream equipment. After a certain period of time, a drain in the pipeline strainer can be opened to remove the debris in order to avoid excess pressure drop associated with the collection of solids in the straining element. This debris may have become lodged in the straining element, and may not easily be removed. Accordingly, it may be necessary to remove the entire straining element to clean and remove all of the debris therefrom. As will be appreciated, this may be a more time consuming process compared with merely opening a debris drain in the pipeline strainer to allow debris to be removed.
It has been suggested that a pipeline strainer include an integral cleaning tool that is rotated by the flow of fluid through the pipeline strainer. As fluid is passed through the pipeline strainer, the fluid passes an impeller, causing the impeller to rotate. The rotation of the impeller causes a brush on an axle to revolve around the axel. The brush is disposed inside of the straining element and is intended to dislodge materials and debris therein.
While presumably effective for its intended purpose, such a device is only able to be used when fluid is flowing through the pipeline strainer. If there is no fluid moving through the pipeline strainer, the cleaning tool cannot be used to dislodge debris. Thus, in order to be cleaned when there is no fluid, the entire straining element must be removed. Additionally, a device which is driven by the flow of fluid can increase the pressure drop of the fluid passing through the pipeline strainer by impeding the flow path of the fluid with, for example, the impeller.
Therefore, it would be desirable to provide a pipeline strainer that includes an integral cleaning tool which can be utilized both when fluid is passing through the pipeline strainer and when no fluid is passing through the pipeline strainer.
It may further be desirable to provide a pipeline strainer that includes an integral cleaning tool which does not significantly increase the pressure drop of the fluid passed through the pipeline strainer.